Encyclopedias, dictionaries, and biographical and statistical sources are useful starting points when you need some background, or references to a few key articles, or to familiarize yourself with key terms, issues, events, or people.
Handbook of Astrobiology (2019)
Edited by Vera M. Kolb
Substantive chapters covering the field of astrobiology, including the chemical origins of life, prebiotic chemistry, life under extreme conditions, and much more.
Encyclopedia of the solar system (3rd ed., 2014)
Edited by Tilman Spohn, Torrence Johnson and Doris Breuer
An award-winning encyclopedia that covers the origin and evolution of the solar system, historical discoveries, and details about planetary bodies and how they interact. A detailed appendix includes data on planetary missions and fundamental data for planets and satellites. Extensive bibliographies.
Physics of Terrestrial Planets and Moons: volume 10 of the Treatise on Geophysics, 2nd ed. (2015)
This volume of the Treatise on Geophysics discusses fundamental aspects of the science of the planets. To search within this source, search in the parent set, Treatise on Geophysics (on the ScienceDirect website). View article titles
Check out the NASA's Mars Exploration Program site for news, topical overviews, images, and links to specific missions and research programs.
Lunar and Planetary Science Information: Mars - a subsite under the huge NASA umbrella. This site archives all space science mission data for NASA's National Space Science Data Center. Look here for lunar and planetary science data and mission information.